Fully automatic rice cooker

ABSTRACT

The present invention is made for the purpose of providing a full automatic rice cooking apparatus that can automatically carry out all of the steps from rice measuring to rice boiling and further washing of a rice kettle after use. This purpose is achieved by an automatic rice cooking apparatus, where a rice supplier supplies a predetermined amount of rice into a rice kettle, a rice rinsing means rinses the rice, and then a rice boiling means boils the rice while placing the rice kettle at a predetermined position, characterized in that the apparatus comprises a rice kettle washing means for washing an inner wall of the rice kettle  32  placed at the predetermined position after the rice boiling and a controller for controlling the rice supplier, the rice rinsing means, the rice boiling means and the rice kettle washing means. By automatically performing the washing of the rice kettle after use in addition to the rice measuring, the rice rinsing and the rice boiling in a single apparatus, a significant laborsaving in the rice cooking can be produced. Further, it is possible to lower the cost and reduce the size.

TECHNICAL FIELD

The present invention relates to an automatic rice cooking apparatusthat can cook rice with no need of manual work.

BACKGROUND ART

As a rice cooking apparatus that automatically carries out a series ofsteps from rice measuring to rinsing and further boiling of rice,various types have been proposed so far. None of such apparatuses isprovided with a means for washing a rice kettle after bringing outboiled rice. Therefore it is necessary to manually wash a rice kettle,which prevents enough laborsaving.

In the Japanese Unexamined Patent Publication No. H7-231847 is proposedan automatic washing device for a rice cooker that automatically washesa rice kettle. This publication discloses an automatic rice cookingsystem with an assembly line from rice measuring to rice boiling andfurther rice kettle washing, where the washing device is used incombination with a rice rinsing device, a rice boiling device, etc. Thisautomatic rice cooking system is intended for use in large-sizedfacilities including a school lunch center and also requires anindividual device to be provided in each step. Thus, the automatic ricecooking system is not suitable for use in a house, a small-sized shop, asmall-scale facility, etc. due to its large space and high expenditurefor installation.

In view of the above problems, an object of the present invention is toprovide a low-cost and small-sized full automatic rice cooking apparatusthat automatically performs washing of a rice kettle after use inaddition to measuring, rinsing and boiling of rice in a singleapparatus, so that it can produce a significant laborsaving in the ricecooking.

DISCLOSURE OF THE INVENTION

The present invention provides an automatic rice cooking apparatuscarrying out a series of steps while placing a rice kettle at apredetermined position, provided with a water supplier for supplyingwater into the rice kettle and a discharger for discharging watersupplied into the rice kettle and/or others to the outside, where a ricesupplier supplies a predetermined amount of rice into the rice kettleand then a rice boiling means boils the rice, characterized in that theapparatus comprises a rice kettle washing means for washing an innerwall of the rice kettle placed at the predetermined position after therice boiling and a controller for controlling the water supplier, thedischarger, the rice supplier, the rice boiling means and the ricekettle washing means.

In the case of using rinsing-free rice (or “Musenmai”), any means otherthan those above is not necessary. But the above rice cooking apparatusmay further include a rice rinsing means so as to also use normal rice.Here, it is preferable that the controller can predetermine whether tocarry out the rinsing step and a non-rinsing mode is selectableparticularly in using the Musenmai.

Preferably, the rice supplier includes a rice container for storing riceand a measuring unit for measuring rice supplied from the rice containerand further supplying the rice into the rice kettle, which can save thelabor of measuring rice and putting it into the rice kettle in everyrice cooking.

The water supplier is intended for supplying water into the rice kettlewhen in the boiling, the washing and, if necessary, the rinsing. On theother hand, the discharger is intended for discharging the water and/orothers from the rice kettle after carrying out those steps.

Preferably, the water supplier includes a water meter for measuring apreset amount of water and a feed-water unit for feeding the watermeasured by the water meter into the rice kettle. The water supplier maybe provided separately for the rinsing and the washing or constructed tobe in common use for both of them.

Preferably, the discharger includes a suction pipe vertically movable tothe lower limit level slightly above an inner bottom surface of the ricekettle, a suction pipe driver for vertically moving the suction pipe anda pump for sucking up water within the rice kettle, possibly containingleftover rice, through the suction pipe.

When in rinsing rise, the above suction pipe is set at the lower limitposition where its tip is located slightly above the inner bottomsurface of the rice kettle so as not to suck up the rice as well as thewater. The tip of the suction pipe is spaced apart from the inner bottomsurface of the rice kettle at such a distance that prevents entry of therice. When in washing the rice kettle, provision is preferably made asfollows. The tip of the suction pipe is first located above the lowerlimit position so as to easily suck up water containing leftover rice,and then lowered gradually. At the stage of draining the whole waterwithin the rice kettle after completion of the final washing, the tip ofthe suction pipe is lowered to the above lower limit position, so thatthe remaining water is minimized.

For the rice kettle washing means, any kind of means can be adopted ifit is electrically controllable, such as a means including an electricbrush etc. that moves along an inner wall of the rice kettle or a meansfor separating leftover rice attached to the rice kettle by slightlygiving ultrasonic vibration to the water and leftover rice within therice kettle.

The rice rinsing means and the rice kettle washing means may bedifferent from each other. However, in the case of using ultrasonicwaves for the washing means, the washing means can be constructed toserve as the rinsing means. With such a construction, bran and/or dirtcan be removed from the surface of the rice by slightly givingultrasonic vibration to the water and rice within the rice kettle whenin rinsing rice. Owing to the above construction, it is possible toreduce the number of parts, lower the manufacturing costs and downsizethe apparatus.

In the case of performing the ultrasonic washing, it is preferable toadopt such a construction where the ultrasonic waves are generated by aplurality of ultrasonic transducers equally arranged around theperiphery of the rice kettle. This allows the ultrasonic waves to betransmitted equally to the water and rice within the rice kettle.Therefore, a high washing effect can be obtained.

In accordance with the present invention, the full automatic ricecooking apparatus includes the controller for controlling the ricesupplier, the rice boiling means, the rice kettle washing means, thewater supplier, the discharger and, if necessary, the rice rinsingmeans. The controller performs each control of those means, which makesit possible to automatically carry out the respective steps of the ricesupply, the rinsing, the boiling and the washing as well as toautomatically switch between those steps, with no need of manual work.Preferably, the controller can predetermine whether to carry out therinsing step and a non-rinsing mode is selectable particularly in usingthe Musenmai, as described above. More preferably, a finish time of theboiling step and the amount of boiled rice is set up so that itautomatically leads to setting the amount of rice and watercorresponding to the above settings as well as the time required for therespective steps of measuring, rinsing, soaking, heating and steaming ofrice.

It is preferable that the boiling means, composed of a rice cooker mainbody with a heater, a rice kettle and a lid, is movable horizontally.The rice cooker main body movable horizontally makes it easy to bringout boiled rice and the lid movable horizontally makes it easy toperform the respective operations of the rice supply as well as thewater supply and the water discharge.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional side view of a full automatic rice cookingapparatus embodying the present invention.

FIG. 2 is a front view of the embodiment.

FIG. 3 is an enlarged view of the measuring unit according to theembodiment, where (a) is a sectional side view and (b) is a sectionalfront view.

FIG. 4 is a sectional side view of the embodiment when dischargingwater.

FIG. 5 is a sectional side view of the embodiment with the boiling meanspulled out.

FIG. 6 is a block diagram showing a relationship between the controllerand each other means.

BEST MODE FOR CARRYING OUT THE INVENTION

The best embodiment of the present invention is described below,referring to the drawings. In the following description, the left handof FIG. 1 is defined as a front side and the right hand of FIG. 1 isdefined as a backside.

A full automatic rice cooking apparatus 10 of the present embodimentincludes a rice supplier 20, a rice boiling means 30, a ultrasonicgenerator 40, a water supplier 50, a discharger 60, a controller 70 anda casing, performing the rice rinsing and the rice kettle washing bymeans of ultrasonic waves.

The above casing is composed of a bottom panel 81, a front panel 82, aback panel 83, a right side panel 84, a left side panel 85 and a toppanel 86, having an opening for taking a rice cooker main body out f thecasing on the lower part of a foreface of the casing.

The top panel 86, serving as a lid covering the rice container, needs tobe removed when in supplying rice into the rice container. Therefore,the top panel is attached so that it can open and close.

The rice boiling means 30 includes a rice cooker main body 31, a ricekettle 32, a heater 33, a lid 34, a slide table 35, a rice cooker sliderail 36, a slide table driver 37, an extension shaft 38, a lid sliderail 39 and a slide arm 39 b. The rice cooker main body 31 encloses therice kettle 32 with no space between. The heater 33 for heating the ricekettle at the time of boiling rice is provided at the bottom of the ricecooker. The rice cooker slide rail 36 is provided on the bottom panel 81of the above casing. The slide table 35 is slidably mounted on the ricecooker slide rail 36 so that it can move back and forth in a horizontaldirection with the rice cooker main body 31 mounted thereon. Theextension shaft 38, fixed to the center of the upper face of the lid 34,is slidably connected to the lid slide rail 39 via the slide arm 39 b.The extension shaft 38 is intended for vertically moving the lid 34 andthe lid slide rail 39 is intended for moving the lid 34 back and forthin a horizontal direction.

The ultrasonic generator 40, provided with a plurality of ultrasonictransducers 41 and an inverter (not shown), is constructed so that theinverter controlled by the controller 70 gives high-frequency power tothe ultrasonic transducers 41. The ultrasonic transducers 41 are equallyarranged in the rice cooker main body 31 and attached so that itssurface for the ultrasonic generation contacts the rice kettle 32.

The rice supplier 20 includes the rice container 21 and the measuringunit 22. The rice container 21 is located above the rice cooker mainbody 31. The container has a bottom surface formed in a tapered shape,so that the rice naturally gathers into a cylindrical rice supply port23 formed integrally with the rice container 21. The measuring unit 22includes the rice supply port 23 and a measuring drum 24 provided insidethe rice supply port 23. FIG. 3 shows the measuring drum 24, shaped likea waterwheel. The measuring drum 24 has such a construction where thecentral parts of two disks 24 a are connected to each other by a hollowbearing 24 b and a space between the two disks 24 a is divided by eightvanes 24 c with the circumferential surface open. Each of the two disk24 a has a hole in its center, positioned corresponding to the hollowpart of the bearing 24 b. A shaft 24 d is inserted into the hole and thehollow part of the bearing 24 b. The above-constructed measuring drum24, rotatable around the shaft 24 d, is attached to the inside of therice supply port 23. Thus, a specific amount of rice enters the spacesbetween the vanes 24 c and the two disks 24 a, and then is dischargedfrom the rice supply port 23 to the outside by rotation of the measuringdrum 24. An end of the shaft 24 d is connected to a rotation shaft (notshown) of a motor 24 e. Therefore, the amount of rice discharged fromthe rice supply port 23 can be adjusted through rotation control of themotor 24 e by the controller 70.

The water supplier 50, located below the rice container 21, includes awater meter 51 and a feed-water unit 52. The water supplier 50 isconstructed to supply water into the rice kettle 32 through thefeed-water unit 52, controlling the water supply by the water meter 51.The water meter 51 is composed of a decompression valve 53 for adjustingthe pressure of water supplied from the outside, a tank 54 fortemporarily reserving the water and an electromagnetic valve 55 forcontrolling the water supply from the tank 54 to the feed-water unit 52.It is possible to control the water supply to the feed-water unit 52 byadjusting the open/close time of the electromagnetic valve 55. Thefeed-water unit 52, as a tubular structure to feed water from the watermeter 51 to the rice kettle 32, slopes downward so as to cause thesmooth flow of water. The tip of the feed-water unit 52 is locatedalmost above the center of the rice kettle 32, so that the water isassuredly fed from the feed-water unit 52 into the rice kettle 32.

The discharger 60 is composed of a suction pipe 61, a suction pipedriver 62, a hose 63, a pump 64 and a drain pipe 65. The suction pipe 61is arranged so that a suction port 66 at the lower end is substantiallyin the center of the rice kettle 32 from a top-view point and isattached so as to be vertically movable by the suction pipe driver 62provided at the front part of the lid slide rail 39. The suction pipe 61is held above the rice cooker main body 31 when not in use. When in use,the suction pipe 61 can be lowered to the inside of the rice kettle 32.An upper end of the suction pipe 61 is connected to the hose 63 and theother end of the hose 63 is connected to the suction side of the pump 64provided at the lower part of the inside of the back panel 83. The drainside of the pump 64 is connected to the drain pipe 65 passing throughthe back panel 83, which construction allows the waste water to be letout.

The controller 70 for controlling each of the above means is composed ofa control unit 71, an operation panel 72 and a power unit 73. Thecontrol unit 71 includes a control circuit. The operation panel 72 isprovided with a rice cooking switch, a rice kettle washing switch, arice cooking unit shift switch and a stop switch. The rice cookingswitch sends a cooking start signal to the control unit 71, the ricekettle washing switch sends a washing start signal to the control unit71, the rice cooking unit shift switch sends the control unit 71 asignal for moving the slide table 35 back and forth, and the stop switchsends the control unit 71 a signal stopping the operation of the fullautomatic rice cooking apparatus 10. The control unit 71 receives thesignals from the respective switches and then runs predeterminedprograms. Each of the above means thus carries out the rice cookingsteps in series.

In the present embodiment, each part of the rice cooking apparatusincludes a detector for detecting completion of the operation (notshown). When each part completes the operation, a signal indicating thecompletion is sent to the above control unit.

The rice cooking steps according to the present invention are describedin the following.

At the time before the cooking is started, the rice cooking apparatus 10of the present invention is in such a state where the rice cooker mainbody 31 is closed by the lid 34 and the suction pipe 61 remains restingup above, as shown in FIG. 1.

When the operator operates the rice cooking switch of the operationpanel 72, the rice cooking apparatus 10 starts a series of the works forthe cooking. First, the control unit 71 receives the cooking startsignal and then sends a contraction signal to the extension shaft 38fixed to the upper face of the lid 34. The extension shaft 38 contractsin response to the contraction signal, whereby the lid 34 moves upward.When the extension shaft 38 stops the contraction at a predeterminedposition, the slide arm 39 b slides backward along the lid slide rail39. Thus, the extension shaft 38 and the lid 34 fixed to the slide arm39 b moves backward. When the slide arm 39 b stops at a predeterminedposition, the detector detects it and then sends the stop signal to thecontrol unit 71. Receiving the stop signal, the control unit 71 sends asignal to the suction pipe driver 62, whereby the suction pipe driver 62brings the suction pipe 61 down to the lower limit position. The lowerlimit position is preset so that the suction port 66 at the tip of thesuction pipe is spaced apart from the inner bottom surface of the ricekettle 32 at such a distance that allows only the water to be sucked inwhile preventing the rice from entering the suction port 66.

The preparations for rinsing the rice are thus completed, and then therice supplier 20 starts the supply operation in such a state as shown inFIG. 4. First, the control unit 71 sends a signal to the motor 24 eperforming rotation control of the measuring drum 24, so as to rotatethe rotation drum a preset number of times. The measuring drum 24 isconstructed so that a specific amount of rice enters the spacesdelimited by the two disks 24 a and the vanes 24 c. By rotation of themeasuring drum 24, the amount of rice dependent on the rotation numbersis discharged from the rice container 21 through the rice supply port 23into the rice kettle 32. The rotation numbers of the measuring drum 24can be controlled by the motor 24 e. Therefore, the rotation control ofthe motor 24 e enables a preset amount of rice to be measured. Thepreset amount of rice is supplied into the rice kettle 32 when the motor24 e of the measuring drum 24 is stopped. Then, the stop signal is sentto the control unit 71.

When the above rice supply operation is finished, subsequently, thewater supplier 50 starts the supply operation. In response to a signalfor opening the electromagnetic valve 55 sent by the controller 70, theelectromagnetic valve 55 is opened and the water supplied from theoutside of the rice cooking apparatus 10 is fed through the feed-waterunit 52 into the rice kettle 32. The decompression valve 53 adjusts thepressure of the water, flowing from the outside into the rice cookingapparatus 10, to a constant level, so that the constant amount of waterpasses through the electromagnetic valve 55 in unit time. Thus, byadjusting the open time of the electromagnetic valve 55, it is possibleto adjust the amount of water supplied into the rice kettle 32. When apreset period of time passes since the electromagnetic valve 55 isopened, the control unit 71 sends the electromagnetic valve 55 a closesignal for the electromagnetic valve 55. Accordingly, the water supplyto the rice kettle 32 is finished.

When the above water supply operation is finished, the ultrasonicgenerator 40 starts the rice rinsing operation. First, the control unit71 sends a signal to the inverter for controlling the ultrasonictransducers 41, and the inverter gives high-frequency power to theultrasonic transducers 41. The ultrasonic transducers 41 change thereceived high-frequency power into ultrasonic waves, so as to giveultrasonic vibration to the rice and water within the rice kettle 32therethrough. Thereby, bran and/or dirt can be removed from the surfaceof the rice. When a preset period of time passes since the rinsing isstarted, a signal indicating the end of the rinsing is sent from thecontrol unit 71. Accordingly, the rinsing by the ultrasonic transducers41 is finished.

Receiving a signal indicating that the rinsing has been finished, thecontrol unit 71 operates the pump 64. The water used for the rinsing issucked up from the suction port 66 through the hose 63 and the pump 64to the outside of the rice cooking apparatus 10. For adequately rinsingthe rice, a series of the steps including the water supply, theultrasonic rice rinsing and the water discharge are repeated a presetnumber of times.

When the final water discharge is completed after the rinsing operationis performed a preset number of times, the control unit 71 sends thesuction pipe driver 62 a signal for raising the suction pipe 61. Whenthe suction pipe 61 is raised and then stopped at a predeterminedposition, the control unit 71 lets the electromagnetic valve 55 beopened for a specific period of time. Thus, the amount of water requiredfor the boiling is supplied into the rice kettle 32. Receiving a signalindicating that the water supply has been completed, the control unit 71sends a signal for moving the slide arm 39 b forward. Thus, the slidearm 39 b as well as the extension shaft 38 and the lid 34 fixed to theslide arm 39 is moved forward and then stopped almost immediately abovethe rice cooker main body 31. After receiving a stop signal, the controlunit 71 sends an extension signal to the extension shaft 38. Byextension of the extension shaft 38, the lid 34 fixed to the lower endof the extension shaft 38 is lowered and then mounted on the rice cookermain body 31. Through the above process, the preparations for boilingthe rice are completed.

Receiving a signal indicating that the lid 34 has been stopped, thecontrol unit 71 sends the heater 33 a signal for the boiling. In advanceof that, the rice is soaked for a specific period of time. When theboiling is finished, the control unit 71 sends the heater 33 a signalfor the heat retention in response to a signal indicating that theboiling has been finished. When the rice cooker main body 31 comes intoa heat retention mode, the rice cooking apparatus 10 of the presentembodiment once brings a series of the steps to an end.

When bringing out the boiled rice, the operator operates the ricecooking unit shift switch of the operation panel 72, so as to send thecontrol unit 71 a rice cooking unit shift signal. Receiving the shiftsignal, the control unit 71 first sends to the extension shaft 38 acontraction signal. By contraction of the extension shaft 38, the lid 34is raised and then stopped at a predetermined upper limit position.Receiving a signal indicating that the lid has been stopped, the controlunit 71 then sends the slide table driver 37 a signal for moving theslide table 35 forward. Receiving the signal, the slide table driver 37moves forward the slide table 35 mounted with the rice cooker main body31 and then stops it at a predetermined position. Thereby, the ricecooker main body 31 is pulled out to the front side of the rice cookingapparatus 10, as shown in FIG. 5, so that the boiled rice can be broughtout.

After bringing out the boiled rice, the operator operates the ricecooking unit shift switch of the operation panel 72 again, so as to senda signal for moving the slide table 35 backward from the control unit 71to the slide table driver 37. In response to that, the slide table 35 ismoved backward and then stopped at a predetermined position. Receiving asignal indicating that the slide table 35 has been stopped, the controlunit 71 sends an extension signal to the extension shaft 38, so that thelid 34 is lowered to close the rice cooker main body 31. Thus, the stepfor housing the rice cooker is finished.

When washing the rice kettle 32 after bringing all of the boiled riceout, the operator first operates the rice kettle washing switch of theoperation panel 72, so as to send the control unit 71 a start signal forthe rice kettle washing. Receiving the start signal, the control unit 71sends a signal to the extension shaft 38 and the slide arm 39 b, asdescribed above. In response to that, the lid 34 is moved upward as wellas backward and then stopped at a predetermined rear position. Receivinga signal indicating that the lid 34 has been stopped, the control unit71 then opens the electromagnetic valve 55 for a specific period oftime, so as to supply water into the rice kettle 32 to a full waterlevel. Receiving a signal indicating that the water supply has beencompleted, the control unit 71 moves the lid 34 forward and downward toclose the rice cooker. When the lid 34 stops moving downward, thecontrol unit 71 sends a signal to the inverter. The inverter supplieshigh-frequency power to the ultrasonic transducers 41. The ultrasonictransducers 41 change the power supplied by the inverter into ultrasonicwaves, so as to give ultrasonic vibration to the water and leftover ricewithin the rice kettle 32. Thus, the leftover rice adherent to the ricekettle 32 and the lid 34 is separated, so that it comes to float orsettle down in the water.

After a preset period of time, the ultrasonic transducers 41 finish thewashing work, and a signal indicating that the washing has been finishedis sent to the control unit 71. In response to that, the control unit 71raises the lid 34 again and then put it on standby at the rear position.Receiving a signal indicating that the lid 34 has been stopped, thecontrol unit 71 then sends the suction pipe driver 62 a signal forlowering the suction pipe. In response to that, the suction pipe driver62 lowers the suction pipe 61 to the inside of the rice kettle 32 andthen stops it at a predetermined position. The suction port 66 ispositioned at a level above the lower limit position so as to easilysuck in the leftover rice contained in the washing water. Receiving asignal indicating that the suction pipe 61 has been stopped, the controlunit 71 drives the pump 64 and discharges the water containing theleftover rice. For adequately washing the rice kettle, a series of thesteps including the ultrasonic washing and the water discharge arerepeated a preset number of times, while the suction pipe 61 is loweredgradually. At the stage of draining the water within the rice kettle 32after the final washing, the suction port 66 is close to the bottom ofthe rice kettle 32 to the minimum, so that the remaining water isminimized.

After the rice kettle washing operation is performed a preset number oftimes, a signal indicating that the water discharge has been finished issent to the control unit 71. In response to that, the control unit 71moves the suction pipe 61 upward and stops it at a predeterminedposition. Receiving a signal indicating that the suction pipe 61 hasbeen stopped, the control unit 71 sends the heater 33 a heating signalfor a preset period of time, so as to dry the rice kettle 32. After thepreset period of time, the control unit 71 finishes the step of dryingthe rice kettle by stopping sending the heating signal. Then, thecontrol unit 71 lowers the lid 34 to closes the rice cooker main body31.

According to the above, the full automatic rice cooking apparatus of thepresent embodiment finishes all of the steps from the rice measuring tothe rice boiling and then the rice kettle washing.

As described above, the rice cooking apparatus of the present embodimentautomatically performs the washing of the rice kettle after use inaddition to the respective steps required for completing the ricecooking, so that it can produce a significant laborsaving in the ricecooking. By adopting such a construction where the washing means servesas the rinsing means, it is possible to reduce the number of parts,lower the manufacturing costs and downsize the apparatus. Since the ricecooking apparatus of the present embodiment includes the controller 70for controlling the respective means, it is possible to automaticallyswitch between the above steps with no need of manual work. Therefore, afurther laborsaving can be attained.

Since a plurality of the ultrasonic transducers 41 equally arrangedaround the periphery of the rice kettle are used as the ultrasonicgenerator 40 for the rice rinsing and the rice kettle washing, the riceand water within the rice kettle or the leftover rice adherent to therice kettle is equally given ultrasonic vibration. Therefore, anadequate rinsing/washing effect can be obtained. In the rice cookingapparatus of the present embodiment, each part of the apparatus includesa detector for detecting completion of each operation and sending asignal to the control unit. The control unit receives a signalindicating that the operation has been completed, and then outputs asignal starting the next operation. However, it is possible to adoptsuch a construction where the above detector is not provided. In thiscase, when the control unit finishes the instruction of thepredetermined operation or when a preset period of time passes since theoperation is started, the control unit automatically outputs a signalstarting the next operation

1. An automatic rice cooking apparatus carrying out a series of stepswhile placing a rice kettle at a predetermined position, provided with awater supplier for supplying water into the rice kettle and a dischargerfor discharging water supplied into the rice kettle and/or others to theoutside, where a rice supplier supplies a predetermined amount of riceinto the rice kettle and then a rice boiling means boils the rice,characterized in that the apparatus comprises: a rice kettle washingmeans for washing an inner wall of the rice kettle placed at thepredetermined position after the rice boiling; and a controller forcontrolling the water supplier, the discharger, the rice supplier, therice boiling means and the rice kettle washing means.
 2. The automaticrice cooking apparatus according to claim 1, wherein the apparatusfurther comprises a rice rinsing means and the controller operatescontrol so that the rinsing means rinses rice supplied into the ricekettle by the rice supplier and then the rice boiling means boils therice.
 3. The automatic rice cooking apparatus according to claim 2,wherein the controller operates such a control where the rice rinsing bythe rice rinsing means is not performed according to a setting.
 4. Theautomatic rice cooking apparatus according to claim 2, wherein the ricekettle washing means serves as the rice rinsing means, and the watersupplier and the discharger are in common use for the rice rinsing andthe rice kettle washing.
 5. The automatic rice cooking apparatusaccording to claim 1, wherein the rice kettle washing means has a brusharranged in the rice kettle and moving along an inner wall of the ricekettle when washing.
 6. The automatic rice cooking apparatus accordingto claim 1, wherein the rice kettle washing means has an ultrasonicgenerator propagating ultrasonic waves to water supplied into the ricekettle.
 7. The automatic rice cooking apparatus according to claim 6,wherein the ultrasonic generator has a plurality of ultrasonictransducers equally arranged around the periphery of the rice kettle. 8.The automatic rice cooking apparatus according to claim 1, wherein thedischarger has a suction port vertically movable to the lower limitposition above an inner bottom surface of the rice kettle by apredetermined distance.
 9. The automatic rice cooking apparatusaccording to claim 8, wherein the controller controls the discharger sothat the suction port is stopped above the lower limit position when therice kettle washing is started and then lowered gradually to reach thelower limit position when the rice kettle washing is completed.
 10. Theautomatic rice cooking apparatus according to claim 3, wherein the ricekettle washing means serves as the rice rinsing means, and the watersupplier and the discharger are in common use for the rice rinsing andthe rice kettle washing.
 11. The automatic rice cooking apparatusaccording to claim 2, wherein the rice kettle washing means has a brusharranged in the rice kettle and moving along an inner wall of the ricekettle when washing.
 12. The automatic rice cooking apparatus accordingto claim 3, wherein the rice kettle washing means has a brush arrangedin the rice kettle and moving along an inner wall of the rice kettlewhen washing.
 13. The automatic rice cooking apparatus according toclaim 2, wherein the rice kettle washing means has an ultrasonicgenerator propagating ultrasonic waves to water supplied into the ricekettle.
 14. The automatic rice cooking apparatus according to claim 3,wherein the rice kettle washing means has an ultrasonic generatorpropagating ultrasonic waves to water supplied into the rice kettle. 15.The automatic rice cooking apparatus according to claim 4, wherein therice kettle washing means has an ultrasonic generator propagatingultrasonic waves to water supplied into the rice kettle.
 16. Theautomatic rice cooking apparatus according to claim 2, wherein thedischarger has a suction port vertically movable to the lower limitposition above an inner bottom surface of the rice kettle by apredetermined distance.
 17. The automatic rice cooking apparatusaccording to claim 3, wherein the discharger has a suction portvertically movable to the lower limit position above an inner bottomsurface of the rice kettle by a predetermined distance.
 18. Theautomatic rice cooking apparatus according to claim 4, wherein thedischarger has a suction port vertically movable to the lower limitposition above an inner bottom surface of the rice kettle by apredetermined distance.
 19. The automatic rice cooking apparatusaccording to claim 5, wherein the discharger has a suction portvertically movable to the lower limit position above an inner bottomsurface of the rice kettle by a predetermined distance.
 20. Theautomatic rice cooking apparatus according to claim 6, wherein thedischarger has a suction port vertically movable to the lower limitposition above an inner bottom surface of the rice kettle by apredetermined distance.
 21. The automatic rice cooking apparatusaccording to claim 7, wherein the discharger has a suction portvertically movable to the lower limit position above an inner bottomsurface of the rice kettle by a predetermined distance.